cmd/go: ensure streaming test's stdout, stderr are same as cmd/go's

Fixes #18153

Change-Id: Ie8a32dd6fe306f00e51cde77dd4ea353f7109940
Reviewed-on: https://go-review.googlesource.com/34010
Reviewed-by: Ian Lance Taylor <iant@golang.org>

1 files changed, 39 insertions, 0 deletions

diff --git a/src/cmd/go/testdata/testterminal18153/terminal_test.go b/src/cmd/go/testdata/testterminal18153/terminal_test.go
new file mode 100644
index 0000000000..d662e55ee5
--- /dev/null
+++ b/src/cmd/go/testdata/testterminal18153/terminal_test.go
@@ -0,0 +1,39 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build linux
+
+// This test is run by src/cmd/dist/test.go (cmd_go_test_terminal),
+// and not by cmd/go's tests. This is because this test requires that
+// that it be called with its stdout and stderr being a terminal.
+// dist doesn't run `cmd/go test` against this test directory if
+// dist's stdout/stderr aren't terminals.
+//
+// See issue 18153.
+
+package p
+
+import (
+	"syscall"
+	"testing"
+	"unsafe"
+)
+
+const ioctlReadTermios = syscall.TCGETS
+
+// isTerminal reports whether fd is a terminal.
+func isTerminal(fd uintptr) bool {
+	var termios syscall.Termios
+	_, _, err := syscall.Syscall6(syscall.SYS_IOCTL, fd, ioctlReadTermios, uintptr(unsafe.Pointer(&termios)), 0, 0, 0)
+	return err == 0
+}
+
+func TestIsTerminal(t *testing.T) {
+	if !isTerminal(1) {
+		t.Errorf("stdout is not a terminal")
+	}
+	if !isTerminal(2) {
+		t.Errorf("stderr is not a terminal")
+	}
+}